1. Field of the Invention
A truss element positioning clamp for use on a truss fabrication table to position a truss element in a preselected position.
2. Description of the Prior Art
Numerous jigs and other positioning or alignment systems have been developed for use in fabricating or assembling trusses.
U.S. Pat. No. 5,816,300 discloses a convertible woodworking jig comprising multiple components suited to making specialty woodcuts necessary for the manufacture of rails and stiles of cabinet doorframes from standard milled wood stock. The jig has a base having a planar work surface, a first fence having a first straight edge, and a second fence with a second straight edge, between which edges a first cam assembly is medially positioned. The cam body is rotatably positionable for wedging a freely positionable pressure block tight against one of either the first straight edge or the second straight edge. The work piece being so secured, a biscuit slot may be cut into the mitered end by use of a guide assembly disposed at an operative end of the second fence, which assembly closely guides a hand-held, power cutting tool at a predetermined angle formed relative to the plane of said second straight edge. The second fence further includes a third straight edge against which a stop assembly having a stop wall is positioned near a free end of the second fence. At the operative end of the second fence, a second cam assembly is positioned adjacent the third straight edge, which assembly can be manually operated to wedge tight a work piece positioned against the stop wall. The work piece is then ready for slotting by a hand held router.
U.S. Pat. No. 5,608,970 teaches a quick release clamp for clamping frame members of a roof truss frame on a roof truss frame table to permit fabrication of roof truss frames. The clamp comprises a moveable clamping jaw, a threaded clamping shaft, and a threaded clamping nut. The jaw is attached to one end of the shaft so that it can rotate with the shaft when the shaft is rotated. The shaft has a stop at the opposite end to the jaw. The nut is screw-threadably attached to the shaft between the jaw and the stop. The jaw is arranged to pass through an aperture in a member to which the clamp is to be attached. The aperture may in fact comprise a slot In a track member. The jaw and the aperture are shaped so that in one angular rotated position of the jaw relative to the aperture the jaw can pass through the aperture but in another angular rotated position relative to the aperture the jaw cannot pass through the aperture. The clamp permits quick release by untightening the nut. In this case, the jaw is moved away from the member to which it is clamped as the nut threadably moves on the shaft. When the nut engages the stop the shaft will be rotated with the nut and thereby rotate the jaw angularly so that it can be drawn through the aperture so that the clamp can then be removed from the member. The clamp can be used as an engagement surface for locating the position of frame members in a roof truss frame on a roof truss frame table used for fabricating the roof truss.
U.S. Pat. No. 5,342,030 shows an assembly table for roof trusses with open parallel channels located on the table which contain jig stops movable along their respective channels by means of a connector head which can be raised and lowered from a gantry carriage located on a gantry which spans the table and runs along tracks located on each side of the table. The respective movements and operation of the gantry, gantry carriage and connector head are controlled by a computer.
U.S. Pat. No. 5,085,414 comprises a jig for forming wooden trusses including a table traversed by upwardly opening channels in which stop units are received to define the structure to formed. Each stop unit includes 2 stop and a clamp member which are adjustable to clamp elements of the channel between them and thereby fits the location of the stop along the length of the channel in which it is received. Each channel carries a scale at one side and the clamp member carries an index mark to be aligned with positions on the scale for accurately locating the stop.
U.S. Pat. No. 4,875,666 teaches a clamp for holding lumber which is used to form roof trusses. A plurality of clamps are placed on a work table oriented to constrain plural pieces of lumber forming the truss until truss plates attach ends of adjacent pieces of lumber. The clamp includes an inner and outer sleeve, the inner sleeve telescopes with respect to the outer sleeve and a spring bias connection exists between the inner and outer sleeve through a threaded shaft which causes the inner sleeve to telescope so that imperfections in the lumber can be accounted for and several identically configured trusses can be formed without removing the clamps from the table.
U.S. Pat. No. 3,367,010 shows a jig for positioning and holding truss members during assembly of a roof truss comprising a series of rails mounted on a support table and on which the truss members are placed, some of the rails being adjustable relative to others and carrying adjustable stops and cam means to locate the truss members in a desired pattern and clamp the truss members together prior to the application of gusset plates to permanently join the truss members. A removable table section permits expansion of the jig to accommodate larger trusses.
U.S. Pat. No. 2,850,926 relates to a vise to hold work-pieces during machining operation wherein pivoted vise jaws are forced together by wedging action, the wedge being actuated by a pneumatic or hydraulic piston.